Machine for grinding or polishing glass.



No.761,59'7. l PATENTEDMAY81, 1904.

11.51. MURNAN'E. MAGHINE- FOR GRINDING 0R POLISHING GLASS;

APPLIQATION FILED OCT. 7. 1903. I

"No menu.

4 m: Noums PETERS c0 Pnofou'mo, WASHINOTOIL use .PATENTED MAY 31, 1904. n. J. MURNANE. I I MACHINE FOR GRINDING 0R POLISHING GLASS.

APPLIOATIQII FILE D OCT. 7. 1903. v I

2 SHEETS-8111117112- K0 MODEL.

INVENTR I .M-

wrrunscs Patented May 31, 1904. I

UN TEDSTATES PATENT OFFICE.

DANIEL-J. MURNANE, OF KIRKWOOD, MISSOURI, ASSIGNOR TO ST. LOUIS I PLATE GLASS COMPANY, OF. VALLEYPARK, MISSOURI, A CORPORATION OF MISSOURI.

.- I MACHINEVFOR GRINDING OR POLISHINGQGLASS.

SPECIFICATION forming part of Letters PatentNo. 761,597, dated May 31, 1904.

Application filed October '7, 1903.

ishing machine; and Fig. 2 is a top plan view of the runner, partly broken away. Fig. 3is a plan View of the working face ofthe runner.

My invention relates to machines forgrind ing or smoothing plate-glass, and more specially to machines having gravity-blocks carried'by the runners of the general type shown and described in my Patent No. 723,008, dated March 17 1903.

The'invention' consists in simplifying andimprovingthe gravity-block system by the use of a single block, preferably of annular form, which extends around the center of the runner and is arranged to perform the grinding and smoothing operation, and it further consists in the construction and arrangement of the runner and gravity-block, as hereinafter -more fully described and claimed.

In the drawings, 2 represents the glass-supporting table, which may be removably mount ed on aframe adapted to be rotated, The runners, of which one or more may be'used, though I preferably use two of different diameters, are keyed to vertical shafts 3, journaled in the machine-frame 4:, in such manner that they can be suspended above and lowered upon the surface of the glass by means of lifting-levers or other devices 5 of ordinary form. The shafts 3 are driven by suitable gearing 6,

* preferably so arranged that the runners are rotated at a greater rate of speed than that of the table. Thus the table may be rotated at two or more revolutions per minute, while I prefer to use a peripheral speed of several thousand feet per minute for the runners.

I have shown each runner as having a hub Serial No.1'76,073. (No model.)

7 which is keyed to the vertical shaft 3 and has a series of outwardly-projecting arms 8,

connecting to an outer annulus 9. The lower portion 7 of the hub projects below the supportingannulus and has feather or spline connections 9 with an annular block 10/ I have shown two of these feather or spline connections, which allow the annular block to adjust itself vertically,while causing its rotation when the runner is rotated. The block is preferably built up of ribbed castings, the ribs 11 extending to the outer circular flange or rim 12. I have shown the gravity-block as provided with a surface consisting of wooden blocks or pieces 13, bolted to the under side and receiv- 7 ing the bolts which hold the metal runnerbars 14, constituting the grinding or smoothing surface. The projections which constitute the working face of each runner-bar instead of being square in outline, as heretofore,

are formed with acute angles 6 at their inner end, as shown in Fig. 3, so that square faces are not afforded at those places for lodgment of the abrasive material and the projections will clear themselves therefrom under the centrifugal action of the runner. I am thus enabled to change the abrasive material from coarser to finer grades from time to time, as required, without incurring the damage which results when coarser abrasive adheres to the runner-bars and scratches the glassduring the use of a finer abrasive.

In order .to raise the gravity-block from the glass when the runner is lifted, Ipreferably connect it loosely to the annulus and the runner by swinging eyebolts 15, extending through holes or slots in the annulus and having adjustable nuts or upper portions. As these bolts pass loosely through the supporting ring or annulus, the block can rest by gravity upon the glass,and thereby adjust itself to the glasssurface,and by adjusting the bolts the face of the block can be brought to a position of perfect parallelism with the glass.

In operating the machine the table with the glass secured thereon is brought under the runners, and the runners are lowered, so that 5 then rotated, while the table is also rotated or, if desired, given a reciprocatory or other movement.

The advantages of my invention result from the simplifying of the. system, the rapidity of I grinding, and the gravity adjustment of the block, which reduces liabilty of breaking or injuring the glass. It will be noted that the gravity-block is held by the connections in its own horizontal plane, so that it will maintain a position parallel to the surface to be ground.

Many changes may be made in the form and arrangement of the table, the runners, the blocks, and their connections without de parting from my invention.

I claim l. A grinding or polishing runner comprising a driving-frame, and an annular gravityblock rotated by said frame and arranged to 5 adjust itself by gravity; substantially as described.

2. Arotary grinding or polishing runner having a driving-frame, and an annular gravity-block connected with the frame in the horizontal plane of the block; substantially as described.

3. A rotary grinding or polishing runner having a driving-frame and an annular gravity-block with a driving connection between said block and frame arranged to allow upand-down movement of the block while rotating; substantially as described.

4. A rotary grinding or polishing runner having an annular gravity-block connected with and rotated by a runner-frame and eapable of vertical movement therein and anindependent suspending device arranged to lift the block with the ru nnerframe; substantially as described.

5. Arotary runner having projecting working faces formed with acute angles at their inner ends; substantially as described.

6. In a grinding or polishing machine, a rotary runner having an annular gravitybloek and a series of vertically-adjustable bolts by which it is adjusted and upheld; substantially as described.

In testimony whereof I have hereunto set my hand.

DANIEL J. MURNANE.

Witnesses:

G. B. BLEMING, H. M. 001mm. 

